Increase in preexisting cellular antigen-combining groups at different times after infection with different viruses

During the course of experiments designed to determine whether infection of normal cells with certain strains of Herpesvirus hominis (HSV) gives rise to a specific neoantigen, presumably characteristic for human malignant cells ("HeLa G"), it was found that the seeming appearance of such a new antigen actually represents only an increase in concentration of previously existing normal antigen groups. The complement fixation tests for this antigen were carried out with antibody prepared by McKenna against a fraction, purified with the fluorocarbon genetron, from HeLa cells. This antibody reacted with extracts of tissue culture cells derived from various human malignant tumors and from the spontaneously transformed WISH cell line, originally derived from normal human amnion, but not with cells derived from early-passage cultures of normal human kidney, or from primary cultures of young rabbit kidney or new-born guinea pig kidney. Infection of rabbit and guinea pig kidney tissue culture cells with HSV strains derived from brain or lip lesions at a high input multiplicity of virus failed to yield the "G" antigen. Infection of human kidney tissue culture cells with the same HSV strains yielded two units of the "G" antigen at 6 hr and 32 units at 24 hr. The conclusion that this was, nevertheless, not a new antigen, but only an increase in amount of preexisting antigen, was based on the demonstration that absorption of the anti-"HeLa G" globulin with uninfected human kidney tissue culture cells completely removed the antibody for the "G" antigen formed during the course of infection with HSV and also that present in uninfected WISH and HEp2 cells. Infection by the same HSV strains of the human WISH cells which have a small amount of preexisting "G" antigen resulted in an increase which was maximal at 24 hr. Infection of WISH cells with vaccinia virus resulted in a rapid increase of "G" antigen, which was demonstrable at 10 min but not at 3, 6, and 24 hr. Absorption of the anti-"HeLa G" globulin with uninfected WISH cells removed the antibody for the G antigen present in the WISH cells before infection as well as after infection with the herpes and vaccinia viruses, and also the antigen present in human tissue culture cells of malignant origin.